The first things that come to mind are
1) io waiting . if cgp in waiting for responses from io it can cause this
type of behavior. Here top is your friend
2) check under monitor -> threads to see what threads are working and in
what state they are when the problem happens. Not easy but the only way to
see what is happening.

> -----Original Message-----
> From: CommuniGate Pro Discussions [mailto:CGatePro@mail.stalker.com]
> Sent: martedì 20 febbraio 2018 03:05
> To: CommuniGate Pro Discussions
> Subject: Re: CGPro regularly disappears for several seconds
>
> It's not a license issue is it? The only thing I can easily think of
> related to a 15
> minute period is an expired license within CGP.
>
>
> On 20/02/2018 4:03 AM, James Moe jimoe@sohnen-moe.com wrote:
> > CGpro v6.1.19
> > linux v4.4.104-39-default x86_64
> >
> > On a regular basis, something like every 10 - 20 minutes, CGPro
> > does... something, for 5 - 15 seconds. During that time it delays
> > interactions with MUAs. From the user's point of view it all they see is
> > the busy spinner. It is annoying.
> > There is nothing in the server's logs to indicate the momentary
> > catatonia. There is nothing in the system logs.
> > This is something that became noticeable several versions ago,
> > somewhere around 6.1.12. It has become more of an issue with each
> upgrade.
> > The only clue I have is what "nmon" displays in its CPU usage: a
> > spike
> > in CPU usage, up to 70%, consisting of wait states. These always occur
> > when CGPro is briefly unavailable.
> > Access to the server is on our local network, not from the Internet.
> > We have a couple of helpers running, one each for DKIM and DMARC.
> >
> > Can anyone suggest what may be happening? Or how to discover what is
> > happening.
> >
>
> --
> Shaun
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